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sailorjim
01-20-2014, 05:55 AM
I've just taken the plunge and bought a 1935 carvel (pitchpine) Broads sailing cruiser |:(.

The hull was painted a couple of years ago above the waterline in two-pack International. The finish is great but there are hairline cracks along the full length of all the (splined) seams. It seems to me that these will have to be dealt with to prevent water getting behing the paint and lifting it off completely. I'm guessing that quite a few other forumites have had to deal with this issue. What's the solution? Routing and Sikkaflexing? Thanks for any and all advice!

Dannybb55
01-20-2014, 06:39 AM
Don't destroy your planking seems for a few cracks. Your planks move with changes in the weather so you will have to get used to it. Pitch pine won't rot if you touch up the paint occasionally or if you leave it raw in the weather. That is the reason carpenters will put up with getting our planes all sticky. Try interlude above waterline seem compound or whit lead putty and some paint. Cracks! In the lopsided paint is normal, keep her wet.

sailorjim
01-20-2014, 07:05 AM
I'm worried less about the underlying wood than about the paint lifting off. Wouldn't dealing with the cracks be a "stitch in time"?

wizbang 13
01-20-2014, 07:41 AM
You say that every seam has full length cracks!!!all jobs are done the same,sounds like the splinting job was hurried. A few cracks,I might say no problem, ignore them, or use a wood stick and push some wax in . I do not like, or use sika type goo. Pics and more info, what are the splines made of, stuff like that. Are the frames and fastenings sound?is the backstays left tight? What COLOR is she?

Bruce

Ian McColgin
01-20-2014, 07:45 AM
Don't reef her out at this point. You'll ruin things.

Some splining is done putting the epoxy on only one side of the spline leaving the other to be a tight seam. Yet even if both sides were epoxied, it sounds as if whoeveer painted after the splining was hoping for a monocoque hull and (no surprise) didn't get it. The paint is too rigid for the surface in the vicinity of the seams.

For now, just wax the hull and get her wet. Once she swells water won't come in and even a little moisture intrusion should not lift the finish if it was done right. If it was done wrong, might as well find that out.

If you ever get to repainting, use something a little more forgiving, less brittle.

G'luck

kc8pql
01-20-2014, 10:23 AM
^^+1.

David G
01-20-2014, 12:44 PM
What Bob said. A rigid film finish - like catalyzed paints - combined with a traditionally planked hull is gonna be an iffy combo at best. I'd put repainting with a more traditional finish on my list of things to do... someday. Meantime, I wouldn't worry about it too much. If the notion of moisture intrustion bothers you... there are various McGiver'ish solutions available. As for touching up the paint... 2-part paints don't take well to touchups. Not that they won't adhere... that's not the issue. The issue is that they don't feather and blend. Your touchups will be quite obvious and noticeable. I could imagine masking and sanding/recoating only the exposed areas... you you at least get a consistent stripe of new material at each seam. But that's a lot of work for a film that is very likely only going to crack again within a season.

Paul G.
01-20-2014, 02:03 PM
What Bob said. A rigid film finish - like catalyzed paints - combined with a traditionally planked hull is gonna be an iffy combo at best. I'd put repainting with a more traditional finish on my list of things to do... someday. Meantime, I wouldn't worry about it too much. If the notion of moisture intrustion bothers you... there are various McGiver'ish solutions available. As for touching up the paint... 2-part paints don't take well to touchups. Not that they won't adhere... that's not the issue. The issue is that they don't feather and blend. Your touchups will be quite obvious and noticeable. I could imagine masking and sanding/recoating only the exposed areas... you you at least get a consistent stripe of new material at each seam. But that's a lot of work for a film that is very likely only going to crack again within a season.

Actually 2 pots touch up extremely well, paint with brush or roller, then rub back through a few fine grit papers, finishing with buffing compound and you will never see the repair.

David G
01-20-2014, 03:01 PM
Actually 2 pots touch up extremely well, paint with brush or roller, then rub back through a few fine grit papers, finishing with buffing compound and you will never see the repair.

I guess you're more adept at the technique than I. My experience is that one can go to the trouble of sanding back what is a much harder surface, do the paint application, rub it all out... and still be left with witness marks.

Which repair, of course, will promptly crack again.

I still say, temporary measures now, and repaint with something more appropriate to your substrate later.

chas
01-20-2014, 04:03 PM
"I've just taken the plunge and bought a 1935 carvel (pitchpine) Broads sailing cruiser ."

Where are you located? There is another thread on paint cracking at seams for a double-planked big schooner in Malta? and I would guess that if you are in the British climate that your fix will be different than hers. / Jim

sailorjim
01-21-2014, 09:13 AM
Thanks to all for your replies and suggestions.

The consensus seems to be that I don't have to worry about water ingress, and that's fine with me :).

I agreed it's a bad idea using paint that neither breathes nor flexes on a carvel hull, even one that's splined.

Lew Barrett
01-21-2014, 12:41 PM
Thanks to all for your replies and suggestions.

The consensus seems to be that I don't have to worry about water ingress, and that's fine with me :).

I agreed it's a bad idea using paint that neither breathes nor flexes on a carvel hull, even one that's splined.

You've got it! You will rarely see a carvel planked boat that doesn't eventually crack paint on at least a few seams, even with forgiving product. With a two part paint, cracking out (and sometimes dramatic lifting) is virtually inevitable.

Jay Greer
01-21-2014, 01:48 PM
One thing about carvel planked hulls is that if the surface paint is not flexible enough, cracking is sure to occur along the seams be they splined or traditionally caulked. My own H28 "Bright Star" has splined seams that are made of glued Port Orford Cedar. The planking is African Mahogany. I can't speak of the glue as the job was done before I purchased the boat. I do know that the topside paint is sprayed LP that was chosen to be flexible. I have owned the boat for over twelve years now and have yet to have a seam crack or any need for repainting. The stuff is flexible and bullet proof! It's longevity has saved us a whole lot of bucks were the boat to need repainting which, it doesn't yet! A light buffing every two years is all that is needed to keep things looking good.
Jay

David G
01-21-2014, 02:52 PM
Jay,

Tell us more about that product, please! All of the Linear Polyurethanes I'm familiar with dry to a very hard, but Very Brittle consistency. If there are some that are formulated for flexibility... that opens some doors for a variety of applications.

Jay Greer
01-21-2014, 06:09 PM
Sorry, I can't share that information, I don't have it. The boat was painted before we bought it. My only way of knowing that the paint is flexible is by seeing how it flexes under strain when the boat is in the slings. It ripples. It twists but, it does not crack or let go; and never has. My best advise would be to contact Basin Marine in Newport Beach CA. They work with a man named George Ball who has recently gone into the paint business with products of his own formulation.
George is the most knowledgable person on modern coating systems I have ever met.
Jay

Paul G.
01-21-2014, 08:09 PM
I guess you're more adept at the technique than I. My experience is that one can go to the trouble of sanding back what is a much harder surface, do the paint application, rub it all out... and still be left with witness marks.

Which repair, of course, will promptly crack again.

I still say, temporary measures now, and repaint with something more appropriate to your substrate later.

David, its all in how you hold your mouth! If in doubt ask a local boat sprayer for a few tips but the idea is to sand the gouge out 20mm or so all around so that the paint fills and fairs nicely. Some paints are superior to apply by hand e.g. perfection but the technique is the same, use a hard block to sand just like youre fairing and you can finish with 1200 on a rubber block, then rubbing compound and polish. You will never see it!